Re: want zombie nnimap groups!

[simon@josefsson.org]

Lars Magne Ingebrigtsen <larsi@gnus.org> writes:

> The other backends (that have the same problem as IMAP) return the
> same list with nn*-request-newgroups as with nn*-request-list; that
> is, all the groups, and then Gnus sorts out the newness issue.
> 
> If the number of groups is (potentially) extremely large, this is
> probably not a good idea for nnimap, but is it likely that the number
> of imap mail groups is extremely large?

I think so, yes.  UoW's imap server (I'd guess it's the most widely
deployed server) export home directories.  Issuing a command to list
all files in even a quite small home directory easily kill performance
on a server (and the client too, of course).

...and listing the groups isn't enough -- nnimap enter each of theese
groups to find out total number of articles and number of unread
articles.  Ideally, this shouldn't be done but fixing it would require
changing the backend interface or making Gnus handle bogus data.

(And we haven't started considering cyclic paths, or when the server
ends up listing / recursively, which normally contain cyclic symlinks,
or if the imap server export the usenet hierachy etc, if the server
contain lots of public groups that many Exchange and Cyrus server
does, etc...)